December is the last chance to influence your 2026 tax bill. These are the actions self-employed Canadians can take before December 31 to legally reduce what they owe in April.
1. Time Your Income Strategically
As a cash-basis sole proprietor, income is taxable in the year you receive it — not when you earned it. If you have invoices due in late December that you could realistically receive payment for in January, delaying the invoice until early January pushes that income into 2027.
This is only beneficial if:
- Your 2026 income is higher than you expect 2027 income to be (lower marginal rate in 2027)
- Delaying does not damage the client relationship or your cash flow
Do not delay essential billing purely for tax purposes — cash flow and client relationships take priority.
2. Accelerate Deductible Expenses
Business expenses paid before December 31 are deductible in 2026. If you are planning to buy equipment, renew subscriptions, or pay professional fees, doing so before December 31 reduces your 2026 taxable income.
- Annual software subscriptions (Adobe, Figma, QuickBooks, etc.)
- Professional association memberships or conference registrations
- Professional development courses with December registration
- Outstanding accountant or lawyer invoices
3. Purchase Required Equipment
Business equipment bought before December 31 qualifies for CCA in 2026, subject to the half-year rule (you claim 50% of the first year’s CCA amount in the year of purchase). A $2,400 laptop in Class 10 at 30% declining balance: first year CCA = $2,400 × 30% × 50% = $360 deduction.
If you need the equipment anyway, buy it before December 31 rather than January — even a $360 deduction is $360 of taxable income reduced.
4. Pay December 15 Instalment
If quarterly instalments are required, December 15 is your final 2026 instalment due date. Paying on time avoids instalment interest. If you have been underpaying through the year and expect a large April 30 balance, consider overpaying your December instalment to reduce interest accumulation from January to April.
5. Review Your GST/HST Account
- Confirm you have correctly categorized zero-rated (international) vs taxable (Canadian) invoices for the year
- Ensure your collected GST/HST is in your tax savings account and not mixed with operating funds
- Check whether your Quick Method election (if applicable) is still more beneficial than the regular method at your current revenue level
6. Check Your 2026 Revenue Against GST/HST Threshold
Review your four-quarter trailing revenue. If you are at $28,000–$29,000 and expect a large January invoice, register for GST/HST now so you are registered when you cross $30,000 — rather than registering retroactively in February.
7. Confirm Your Tax Savings Rate
Use the remaining weeks of December to top up your tax savings account if needed. A useful quick estimate: if your net business income is approximately $80,000, your combined income tax + CPP for an Ontario resident is roughly $28,000–$32,000. Check whether your savings account reflects this.
Frequently Asked Questions
Can I prepay next year’s rent or insurance to deduct it this year?
For most cash-basis sole proprietors, expenses are deductible when paid. Prepaying January 2027 rent in December 2026 is deductible in 2026. The CRA may challenge extremely large prepayments that extend far into the future, but one or two months of prepayment at year-end is commonly accepted in practice.
Should I try to incorporate before December 31 for tax reasons?
If you are considering incorporation and your income in 2026 is high, incorporating before December 31 theoretically lets income earned after incorporation be taxed at corporate rates. However, the timing and structure of mid-year incorporation are complex — a CPA needs to model whether the benefit outweighs the transition costs and complications. Do not incorporate on December 29 without professional advice.
What if I forgot to record some expenses from earlier in the year?
Review your bank and credit card statements for the full year before December 31. Expenses paid earlier in 2026 but not yet recorded in your accounting software are still deductible — they just need to be entered. December is the last chance to ensure your 2026 books are complete before year-end.